recently i did a plugs and wires change...and ran the wires over the valve cover...since then the car will run fine until the engine gets hot...and then the rpm gauge will fluctuate down and then back up to the normal area repeatedly and it feels as if the engine just lost all sorts of power and it drags...i have the wires wrapped with fire sleeving...so i dont think its a problem with heat cycling...i ran the taylor ovc wires that u cut and crimp yourself and i know they are all fine and connected right...and have no idea why i get this power loss and fluctuation in my rpms once the engine gets hot/after running it for about 15 mins....PLEASE HELP!!

 

Sounds like its when it goes into closed loop. But that would begin to point at O2 sensors. Do you get an SES? Are you sure you're not misfiring?

 

yes i am getting an SES light and i hooked up my scan tool and it gave me the code "random/multiple misfire detected" but i replaced my coil today...and it seems to be running a lil better but definitely not top notch...definitely need all the HELP i can get on this one...also, wen i really get on the gas in like 4th gear i can feel a little vibration and not enough acceleration...

 

Did the engine run OK BEFORE you changed the plugs and wires? Why did you change the plugs and wires - any particular problem you were trying to solve, or just routine maintenance?

If the problem appeared only AFTER you swapped out the plugs and wires, and you've got misfires, sounds like there may be a problem with them. Or you pulled a wire or vacuum line off when you were doing the plugs and wires.

 

yeah it ran fine b4 i did the plugs/wires change...so now how do i check to make sure that it is a misfire???....and wen u said i might have pulled a vacuum line or wire off..which ones should i check??

 

o and yes plugs/wires was a routine maintainence thing

 

also..i dont know if this makes a difference or not...the car only starts fluctuating at idle after it is warmed up to about 185 degrees...wen its colder it seems to run fine...but i still have the SES light...

 

ok this morning i checked to make sure all wires and vacuum lines were connected correctly and they were...and i took out the pcm batt fuse for about 5 mins and then put it back in (to reset the pcm and SES light) and then i started the car up and took it for about a 15 min drive around town figuring the light would come back on...but no SES light...and the car seemed to run great until it warmed up to about 180-185....then i noticed the power loss again...but still no SES light....now im very confused and have no clue...PLEASE HELP!!

 

Does your scan tool have "enhanced parameters" capability? If it does, you can pull up the misfire count by individual cylinder. That might indicate if its really random (coil, IC Module, Opti) or cylinder specific (plug, wire, injector).

Things that may have a problem due to heat soak:

-IC Module
-coil
-Opti optical sensor
-wire insulation

Things that may cause temperature sensitive problems:
-faulty coolant temp sensor
-O2 sensor problems

Did you possibly run a plug wire close to and in parallel with anything like the O2 sensor harness, knock sensor harness, etc?

 

its a very good possibility that i could have run it too close to an O2 sensor bc i didnt pay attention to that on the passenger side....wud it make a little click noise like (tick tick tick tick)...and no i dont think my scan tool has "enhanced parameters"...maybe later tonight after work i can take a pic of the wires and the way i ran them and post it on here...

 

If you hear "tick tick tick".... I'm thinking arcing.

Have you tried checking under the hood in the dark, to look for a light show on the wires? Is it possible you have some terminals "loose", either not snapped fully on the plug, or not constructed properly when you assembled your own ends? If you have a gap that the juice has to jump, its going to look for the path of least resistance, and that could cause even brand new wires to start cross-firing and/or arcing to ground.

 

hmm havent checked it in the dark yet but...my drivers side wires are routed over the valve cover and my passenger side just comes up top and then down next to the alternator to the opti...i dont have the passenger side run thru the looms...they are just zip tied together bc i didnt have the time to run them the right way(which i will do next week)...also wen i changed the wires i didnt change the coil wire....could either or both of these situations be what is affecting my car?? also as an update..i do NOT have an SES light anymore but once the car is hot i can feel the power loss (i.e. cant peel wheels, car kind of tugs a little bit thru each gear, and rpms dip down and then back up a little)